baber/WOPTO huggingface dataset:
Patent AT-1373-U1 (AT)
Title: Gerät zum entsalzen und aufbereiten von wasser
IPC: B01J47/00
Filed: 1996-05-14
Abstract: Gerät zum Entsalzen und Aufbereiten von Wasser, insbesondere Brauchwasser von Elektroerosionsmaschinen, bei welchem zwei Ionentauschersäulen (2,3) hintereinandergeschaltet sind, von welchen die eine (2) mit Kationentauschharz und die andere (3) mit Anionentauschharz gefüllt ist, wobei die beiden Ionentauschersäulen (2,3) in einem gemeinsamen, dicht verschlossenen Gehäuse (1) angeordnet sind, und wobei aus dem Gehäuse (1) die Anschlüsse für die Zuleitung (5) und die Ableitung (6) jeder Säule (2,3) dicht herausgeführt sind.
Patent AT-4131-U1 (AT)
Title: Eckenabdichtung einer blockkonstruktion
IPC: E04B2/70
Filed: 1999-11-26
Abstract: Die Erfindung betrifft eine Eckenabdichtung für eine Blockkonstruktion, die in der von zwei Wänden gebildeten Ecke kreuzweise übereinander greifend in Verbrand gebrachte Balken (1, 1) mit je einem Verbandsteil aufweist, sodass die Balken beider Wände dicht übereinander gelegt werden können, wobei das Verbandsteil einen oberen und/oder unteren Ausschnitt an der Verbindungsstelle des Balkens aufweist. Erfindungsgemäß ist vorgesehen, dass an jedem der Balken (1, 1) im wesentlichen im Innenwinkel im Bereich der Verbindungsstelle an der Innenfläche eine Nut (3) ausgebildet ist, wobei diese Nuten der aufeinander geschichteten Balken einen Kanal bilden, in welchem das in Vertikalrichtung zusammenhängende Dichtungsband (4) angeordnet ist.
Patent AT-15992-U1 (AT)
Title: Dirndloberteil mit elastischen Einsätzen
Inventor: MANUELA HUBER
IPC: A41C1/02
Filed: 2018-01-30
Abstract: Dirndloberteil (1), bestehend aus Vorderteil (2) und einem Rückenteil (4) verbunden auf beiden Seiten mit je einem elastischen Einsatz (3), welches sich dadurch um eine oder mehrere Konfektionsgrößen dehnt.
Patent AT-17233-U1 (AT)
Title: Einfassung
IPC: E04D13/147
Filed: 2020-07-17
Abstract: Eine Einfassung (1) zum Einfassen einer quaderförmigen Durchdringung, insbesondere eines Kamins, umfasst ein erstes und ein zweites Einfassungsteil (2, 3), wobei das erste Einfassungsteil (2) an einander parallel gegenüberliegenden Rändern (,4) einer ersten Abdeckplatte (5) erste Führungsprofile (6) aufweist und das zweite Einfassungsteil (3) an einander parallel gegenüberliegenden Rändern (7) einer zweiten Abdeckplatte (8) zweite Führungsprofile (9) aufweist, wobei das erste und das zweite Einfassungsteil (2, 3) jeweils entlang der ersten und zweiten Führungsprofile (6, 9) aus der ersten und zweiten Abdeckplatte (5, 8) aufragende seitliche Wandteile (11, 12) aufweisen und wobei am ersten Einfassungsteil (2) zwischen den seitlichen Wandteilen (11) eine bewegliche Vorderwand (13) aus der ersten Abdeckplatte (5) aufragt und am zweiten Einfassungsteil (3) zwischen den seitlichen Wandteilen (12) eine abtrennbar mit den seitlichen Wandteilen (12) verbundene Rückwand (17) aus der zweiten Abdeckplatte (8) aufragt.
Patent BG-3713-U1 (BG)
Title: Kit of milling tools for forming a conical double-start thread in a medical implant
Inventor: DINCHEV MANOL
IPC: B23G5/18
Filed: 2020-03-24
Abstract: A kit of milling tools for forming a conical double-start thread in a medical implant, according to the utility model, includes a drill bit for drilling a hole, a countersink for determining a hole for milling and a thread milling cutter for cutting a conical double-start thread, as each of the tools consist of a working part (1, 4, 7), a cylindrical gripping part (2, 5, 8) and a transition piece (3, 6, 9). Each of the tools is made of a carbide work piece with a triplex TiCN titanium carbonitride PVD coating.
Patent AT-7677-U1 (AT)
Title: Futterbeutelentleerer
Inventor: BENISEK THOMAS
IPC: B65D33/16
Filed: 2004-03-30
Abstract: Quetschvorrichtung zum Ausdrücken von Futterbeuteln, welche aus zwei parallelen Schenkel (1) besteht und auf einer Seite geöffnet ist. Die geöffnete Seite weist Abschrägungen (2) auf, sodaß die Öffnung sich verbreitert und ein Einfädeln des Futterbeutels erleichtert wird. Die geschlossene Seite ist mit einem Kopf (3) ausgestattet welcher gleichzeitig als Haltegriff dient. Die Quetschvorrichtung ist einteilig und weist keine beweglichen Teile auf.Vorteile:1. Durch die Quetschvorrichtung bleiben Hände bzw. Finger garantiert sauber.2. Mittels Quetschvorrichtung kann man die Futterbeutel portionieren.3. Die Quetschvorrichtung ermöglicht geöffnete Futterbeutel wieder zu verschließen.4. Der Futterbeutel wird restlos entleert und somit nicht zum "Sondermüll".
Patent AT-15121-U1 (AT)
Title: Optisches System für eine LED-Lichtquelle sowie Leuchte mit einem solchen optischen System
Inventor: PATRIK DIPL ING GASSNER
IPC: F21V13/04
Filed: 2013-12-04
Abstract: Die Erfindung betrifft ein optisches System zur Beeinflussung eines, von einer LEDLichtquelle abgegebenen Lichts. Das optische System weist eine Linse zur Beeinflussung des Lichts auf, sowie einen topfartigen Reflektor, durch dessen Form eine Hauptachse festgelegt ist. Der Reflektor weist nach innen weisende, reflektierende Flächenbereiche auf und bildet mit Bezug auf die Hauptachse auf einer ersten Seite eine Lichtaustrittsöffnung. Dabei ist die Linse auf einer, der ersten Seite gegenüberliegenden zweiten Seite des Reflektors angeordnet, und zwar derart, dass das Licht nach Austritt aus der Linse einen Weg zu der Lichtaustrittsöffnung zurücklegt und anschließend durch Letztere hindurch den Reflektor verlässt. Das optische System ist dabei derart gestaltet, dass das Licht auf dem Weg zwischen der Linse und der Lichtaustrittsöffnung zu einem überwiegenden Teil nicht an den reflektierenden Flächenbereichen des Reflektors reflektiert wird und lediglich zu einem weiteren, kleineren Teil an den reflektierenden Flächenbereichen des Reflektors reflektiert wird. Durch diese Gestaltung lässt sich insbesondere erzielen, dass das Lichterscheinungsbild, das sich durch eine Leuchte mit einem solchen optischen System erzeugen lässt, keine oder allenfalls nur reduzierte unerwünschte harte Schattenkanten aufzeigt. Dabei lässt sich dennoch ein Mindestabschirmwinkel für die Lichtabgabe gewährleisten. Auch lässt sich mit dem Reflektor Einfluss auf die Lichtverteilung nehmen.
Patent DE-9400814-U1 (DE)
IPC: A21B3/15
Filed: 1994-01-19
Abstract: The paper (1) is made from a material with anti-sticking properties, or from a base material (2) with anti-sticking coating. One side of the sheet (1) is coated with an absorbent material (4) which is paper, or a cellulose-, cotton-, polymer-, or fibrous material; of organic or inorganic origin. A bonding agent (5), e.g. starch adhesive, unites the absorbent (4) to its backing. This layer has a crepe-, or other expanded structure.
Patent DE-9412530-U1 (DE)
IPC: F15B13/01
Filed: 1994-08-03
Abstract: The hydraulic damper has a second by-pass valve (Z) which is arranged between a control connection (3) of the valve unit (V) and an outlet pipe (9'). The by-pass valve can be switched to a through flow position in the pressure transmitting direction. A transmission piston (K) subject to the control pressure pipe (1) is provided in the by-pass valve. The piston acts on the by-pass valve in accordance with the pressure difference between the control pressure pipe and the outlet pipe in the closing direction.
Patent DE-9422480-U1 (DE)
Title: Implantat für den Zwischenwirbelraum
IPC: A61F2/30
Filed: 1994-09-20
Abstract: Implantat (6) für den Zwischenwirbelraum (25) mit einem quaderförmigen Körper, dessen Kantenlängen quer zu seiner Längsachse verschieden sind und mit einer Vorrichtung (8) an einem hinteren axialen Ende (10) des Implantats (6) zum Ansetzen eines Werkzeuges (9), das eine längsaxiale Kraft überträgt, gekennzeichnet durch eine Vorrichtung am vorderen axialen Ende (12) des Implantats (6) zum Ansetzen des Werkzeuges (9).
Patent DE-20108668-U1 (DE)
IPC: B32B21/08
Filed: 2001-05-22
Abstract: The invention relates to a panel (1) for a floor covering with a layer (2) consisting of a thermoplastic material, which is applied between the underside of the panel (1) and a further layer (3). The further layer consists in particular of a very thin, strong paper impregnated with acrylate.The invention achieves particularly good footfall noise-absorption.
Patent DE-20118240-U1 (DE)
IPC: E04F19/00
Filed: 2001-11-09
Abstract: The plate is an angle section formed from two identical plate components (12, 14). The surface of each plate carries an indicator mark. The mark on the first plate is on its inside surface.
Patent DE-20215997-U1 (DE)
Title: Milk vending machine for dispensing milk or for adding portions of milk to tea or coffee
IPC: G07F13/02
Filed: 2002-10-17
Abstract: The vending machine dispenses portions of milk either as a fluid, cooled or warm, or in the form of cooled or warm foam. The apparatus includes a container (10) for the supply of cold milk. Milk can then be conveyed from the container via an electric heater (18) to a stirrer or foamer and to an outlet. A controller is provided to activate the heater and/or stirrer or foamer as required. A pump may be provided to dispense portions of milk from the container.
Patent DE-20216612-U1 (DE)
IPC: A61K6/04
Filed: 2002-09-27
Abstract: Alloys composed of 35.5 to 62.5 % silver, 4.1 to 11.0 % indium, 5 to 37.0 % gold, 0 to 40.0 % platinum, 0 to 35 % palladium, 0 to 9.5 % zinc, tin, gallium, copper, 0 to 2.0 % iridium, rhenium, rhodium, ruthenium, 0 to 5.0 % boron, cobalt, chromium, iron, germanium, niobium, nickel, silicon, tantalum, titanium, manganese, vanadium, the indicated percentages being percentages by weight. On one hand, such alloys are inexpensive, and on the other hand, their physical properties with respect to the coefficient of thermal expansion make them suitable for veneering. Furthermore, they show a desired yellowish colour and improved corrosion resistance and mechanical properties.
Patent DE-20217286-U1 (DE)
Title: Guide device for machines contains at least two support components movable relatively to each other, of which at least one has at least two guide columns with axes and at least one other has equal number of bearing housings
IPC: B23Q1/26
Filed: 2002-11-09
Abstract: The guide device (1) for machines contains at least two support components (2,5,6) movable relatively to each other, of which at least one has at least two guide columns (3) with axes (A1,A2) and at least one other (5,6) has an equal number of bearing housings (7), in which between stops on both sides a bearing bush is arranged. The bearing bushes are so arranged in their bearing housings with radial clearance, that through the radial clearance both measurement deviations in the distances of the guide columns in a radial direction and also non-straight positions between the guide columns and the bearing housings due to tip movements of the bearing bushes in the bearing housings in relation to the axes are compensated. The radial clearance can amount to between 0.1 and 1.0 mm or 0.02 and 0.1 mm.
Patent DE-20217678-U1 (DE)
Title: Steel support for prefabricated reinforced concrete parts has interconnected flat steel bars extending parallel to one another with at least one steel anchor provided on each steel bar on at least one side face
IPC: E04B5/02
Filed: 2002-11-15
Abstract: The steel support (1) has at least two interconnected flat steel bars (2) extending parallel to one another and standing in the vertical axis. At least one steel anchor (5) is provided on each steel bar on at least one side face. The flat steel bars are connected by the bottom edge at both ends by a steel plate (3).
Patent DE-20219754-U1 (DE)
Title: Tieflochbohrer mit auswechselbarem Schneideinsatz und auswechselbarer Führungsleiste
IPC: B23B51/04
Filed: 2002-12-19
Abstract: Tieflochbohrer mit einem Schneidenträger (1), einem auswechselbaren Schneideinsatz (2) und zumindest einer auswechselbarer Führungsleiste (3, 30), wobei der Schneidenträger (1) für einen vorbestimmten Nenndurchmesserbereich eingesetzt wird, dadurch gekennzeichnet, dass jedem Nenndurchmesser (ND 1  – ND 5 ) in dem Nenndurchmesserbereich (ΔND) ein gesonderter Bausatz aus einem Schneideinsatz (2) und zumindest einer Führungsleiste (3, 30) zugeordnet ist, für den am Schneidenträger (1) feste Anschläge (10, 14, 9) ausgebildet sind.
Patent DE-20301208-U1 (DE)
Title: Combined beach mat and bathing towel of the same size are linked by a hook and loop fastener or sliding clasp fastener
IPC: A45F3/00
Filed: 2003-01-27
Abstract: A beach mat is combined with a bathing towel. The beach mat is the same size as or slightly larger than the bath towel. The mat and towel are linked by a hook and loop fastener or sliding clasp fastener. The combined mat and towel are anchored to the beach by stakes inserted through eyes.
Patent DE-20309081-U1 (DE)
Title: Hanging shelf system for receiving objects such as compact disks and DVDs
IPC: G11B33/04
Filed: 2003-06-12
Abstract: The shelf system for storing CDs, cassettes etc. can be integrated into existing shelves, items of furniture or filing systems by hanging or screwing without the need for its own base or support system. The shelf is made of a single piece.
Patent DE-20310729-U1 (DE)
Title: Height-adjustable outboard motor for water craft, has hoist mounted on boat for vertical lowering and raising of motor
IPC: B63H20/10
Filed: 2003-07-12
Abstract: An outboard motor is designed as a boat drive with power supply via a flexible cable from a power source installed in the boat (1). A lift /hoist (7) is mounted on the boat for approximately vertical lowering of the motor (5) below the level of the boat's keel (12) and lifting of the motor (5) above the level of the keel (12).
Patent DE-20311286-U1 (DE)
Title: Advertising package for bottles comprises plate connecting sleeves which fit over bottles and have conical shape with narrow end upwards, sleeve lodging under collar at top of bottle neck
IPC: G09F23/06
Filed: 2003-07-23
Abstract: Advertising package (1) for bottles comprises a plate (12) which connects sleeves (2 - 2''') which fit over the bottles. These have a conical shape with the narrow end upwards. This lodges under the collar at the top of the bottle neck or its stopper when the package is fitted, preventing theft of individual bottles.
Patent DE-20311591-U1 (DE)
Title: Tool with internally threaded sleeve and screw with hexagonal head is used for screwing in stiff screw or stud and screw has left-hand thread
IPC: B25B31/00
Filed: 2003-07-28
Abstract: The nut (4) has a normal hexagonal head and a shaft with a left-hand male thread. It screws into the upper part (2) of a sleeve (1) with a left-hand female thread. The lower part (3) of the sleeve has a right-hand female thread engaging on a stud with a right-hand male thread. A projection (5) on the bottom of the screw engages on the flat top of the stud.
Patent DE-20313403-U1 (DE)
Title: Fall guard for building sites has barrier element in form of lashing strap which by fastening elements is tensioned between supports serving as post element, with fastening elements comprise hook elements with C-form cross section
IPC: E04G21/32
Filed: 2003-08-29
Abstract: The fall guard (1) for building sites has at least one horizontally extending barrier element fitted between vertical post elements. The barrier element is in the form of a lashing strap (14) which by means of fastening elements (16) is tensioned between supports (12) serving as a post element. The fastening elements comprise hook elements (18) with a C-form cross section which grip round the support or a part of it. The hook elements are fastened to the supports by clamping devices (28,30).
Patent DE-20313905-U1 (DE)
Title: Lighting unit fitted to e.g. wall or ceiling, and based on light-emitting diodes has optical coupling section transmitting light by multiple internal reflection
IPC: F21V7/00
Filed: 2003-09-04
Abstract: The light-directing, optical coupling section (27) has curved inner surfaces (20). Light is led through (27) from the entry surface (28) to the exit surface (30) by multiple reflection on its inner walls.
Patent DE-20315802-U1 (DE)
IPC: A61L2/26
Filed: 2003-10-14
Abstract: The articles (7) are contained in a reflective plastic foil cover (4) with magnetrons (2) in a sterilisation chamber (3) closed by a zip fastener (6) with a simple means to regularly interrupt the radiation to achieve sterilisation. The fastener may have a safety arrangement.
Patent DE-20315890-U1 (DE)
Title: Elektroakustische Wandlereinheit für eine Freisprecheinrichtung
IPC: H04M1/60
Filed: 2003-10-16
Abstract: Elektroakustische Wandlereinheit für eine Freisprecheinrichtung, wobei die Wandlereinheit zur Anordnung im Kopfbereich ausgebildet ist, gekennzeichnet durch einen verformbar, insbesondere elastisch ausgebildeten Schwenkarm (300; 300'; 300"), an dem wenigstens ein Schallübertragungsmittel angeordnet ist, und durch einen an dem Schwenkarm (300; 300'; 300") angeordneten flexiblen Arm (400), an dem wenigstens ein Schallaufnahmemittel (410) angeordnet ist.
Patent DE-20318533-U1 (DE)
Title: Print with design imitating sand effect, especially advertising display, has sand effect provided by tactile particulate material bonded to paper or film
IPC: B44C1/20
Filed: 2003-11-29
Abstract: The sand effect (18) is formed by a particulate material bonded to the paper or film, which provides the print with a tactile effect.
Patent DE-20318685-U1 (DE)
Title: Mat for protection against entry of rodents and other small wild animals into chosen areas consists of galvanized, helically shaped steel wires woven with another
IPC: A01M29/00
Filed: 2003-12-03
Abstract: The mat for protection against entry of rodents and other small wild animals into chosen areas consists of galvanized, helically shaped steel wires woven with another.
Patent DE-29703324-U1 (DE)
IPC: E05D5/14
Filed: 1997-02-25
Abstract: The first half (30) of the hinge (100) is secured to the front surface (2) of the fixed door- or window-frame, and the second half (40) to that of the leaf (20). The first half extends above the second one to accommodate a pin (6) passing through both, and which forms the hinge axis (A). The pin is movable in a straight guide in the transverse direction, so as to adjust the leaf position inside the frame. The external screw (50) adjusting the pin is actuated from the top of the hinge, and its axis can be parallel to the hinge axis. The pin can be accommodated in a bush (8) which is guided in a recess allowing no free movement in the hinge half (42).
Patent IT-BO930065-U1 (IT)
Title: Scopa monolitica in materiale plastico espansocon scheletro in due pezzi.
Inventor: SARTORI FRANCESCO
IPC: A47L/
Filed: 1993-03-25
Abstract: Scopa monolitica in materiale plastico espanso con scheletro in due pezzi, comprendente asta longitudinale inserita in rispettivo forame passante impegnata in una gola provvista inferiormente ad un corpo cilindrico schiacciato a sua volta inserito in rispettivo forame trasversale passante che altresì reca l'innesto per il manico.
Patent IT-CB940002-U1 (IT)
Title: Cassetta per water a vasi comunicanti a due pulsanti avente un solo galleggiante, un solo rubinetto di carico di acqua e un tubo di
Inventor: MARTINO GIUSEPPE
IPC: E03D/
Filed: 1994-03-03
Abstract: Il nuovo trovato per la cassetta di scarico per water deriva dalla cassetta già ideata e progettata da Giuseppe MARTINO e per la quale ottenne il brevetto per modello industriale di utilità n. 0218805 in data 23/10/92 dall'Ufficio Centrale Brevetti di Roma.Il trovato (v; sezione longitudinale) consiste nel caricare e nello stesso tempo scaricare l'acqua del contenitori A e B (A per le urine e B per le feci) aventi un unico rubinetto di carico, un galleggiante e un tubo di scarico.
Patent IT-TN910012-U1 (IT)
Title: Palo per tracciati da slalom sulla neve con relativa bussola fermapalo
Inventor: MICH RENATO
IPC: A63C/
Filed: 1991-10-01
Abstract: La presente invenzione concerne un palo per tracciato da slalom sulla neve, composto dal tradizionale palo il cui puntale risulta ovalizzato e portante in rilievo dei filetti su facce opposte, nonché in una bussola conica avente all'esterno un filetto a dente di sega che infilato e avvitato nella neve la comprime e la plasma, formando un buon ancoraggio.All'interno della bussola vi sono delle nervature longitudinali che formano un foro ovale del diametro leggermente superiore a quello del puntale del palo ovalizzato e che rendono l'interno della bussola parallelo.Le reciproche ovalizzazioni del palo e della bussola consentono facilità di inserimento del primo nella seconda, preventivamente infilata nella neve; il palo viene quindi saldamente bloccato alla bussola mediante rotazione di 1/4 di giro che porta in contrapposizione i due ovali.
Patent IT-TO920134-U1 (IT)
Title: Perfezionamento relativo ai mezzi di scorrimento delle serrande bilan-  ciate di armadi metallici.
IPC: A47B/
Filed: 1992-05-19
Abstract: Mezzi di scorrimento per serrande bilanciate di armadi, particolarmente armadi metallici, comprendenti coppie di cuscinetti/pulegge a gola (8, 9 - 10, 11) sopportate da coppie di staffe opposte (7), due staffe applicate in sommità dei fianchi opposti dell'armadio; ogni coppia di pulegge, due coppie per ogni staffa, essendo impegnata da un anello elastico (12), di sezione circolare, montato a cavaliere delle stesse; ogni anello elastico di diametro tale da sporgere dalle gole delle relative pulegge allo scopo di costituire organi di contatto e di rotolamento per i bordi longitudinali opposti della serranda (2) nei movimenti di apertura-chiusura della stessa; fig. 3,4.
Patent IT-TV930006-U1 (IT)
Title: Struttura portacestini, vassoi o ripiani dotata di due elementi strut-  turali uno fisso e l'altro mobile, inseribile in qualsiasi tipo di
Inventor: CANCIAN PAOLO
IPC: A47F/
Filed: 1993-02-12
Abstract: Il presente trovato ha per oggetto una struttura in tubolare metallico o di altro materiale idoneo ad attrezzare mobile contenitore di dimensioni variabili per una ordinata pratica, razionale sistemazione di prodotti e oggetti di largo consumo. La nostra proposta rappresenta una novità assoluta in merito al funzionamento, rapidità di montaggio e assemblaggio dei pezzi che la costituiscono.E' costituita da due elementi strutturali, uno fisso l'altro movibile mediante mezzi di imperniamento.In questi elementi vengono realizzati dei fori per l'inserimento di cestini e vassoi contenitori.L'elemento fisso viene bloccato attraverso viti al mobile contenitore, mentre quello mobile viene fissato attraverso due staffe angolari di facile applicazione dotate di boccole e controboccole per facilitare la rotazione dei perni. L'elemento mobile è dotato di un dispositivo costituito da una guida e da un pernetto che ha funzione di rendere la rotazione solidale e quella dell'anta del mobile contenitore.
Patent IT-TV940006-U1 (IT)
Inventor: MUSSATO FAUSTO
IPC: B28C5/12
Filed: 1994-02-11
Abstract: Plaster sprayer for applying dry premixed plasters, which includes a chamber (4) for mixing with water and mixture pumping means that are constituted by a tube-and-auger assembly (8,9). The plaster sprayer comprises a jaw (12) which is adapted to temporarily lock the tube-and-auger assembly (8) and is slidingly associated with fixed guiding means (15a,15b). The jaw (12) also interacts with a locking flange that can be removed to allow quick and easy mutual disengagement and engagement of the auger (9) and of the tube. <IMAGE>
Patent IT-VI910077-U1 (IT)
Title: Distanziatore delle setole per la fabbricazione di pennelli
IPC: A46D/
Filed: 1991-08-12
Abstract: Secondo il trovato si realizza un distanziatore (1) delle setole (9) per la fabbricazione di pennelli (10), costituito da un listello in materiale plastico provvisto sulle facce laterali (2) di scanalature (3) fra loro parallele ed ortogonali all'asse longitudinale (4) del listello stesso. Il distanziatore presenta in sezione trasversale all'asse longitudinale (4) una forma simmetrica a base arrotondata (5) con le facce laterali (2) convergenti ad angolo acuto (6) dalla parte opposta della base arrotondata (5). Lo spigolo di fondo (7) di ciascuna scanalatura (3) presenta una curvatura con la concavita' rivolta verso l'esterno.